I actually went to a neurologist a few months after Allie was born because I thought I was losing brain function or suffering some kind of tumor or something. My husband was telling me about entire conversations we had, of which I had literally no memory.
The neurologist saw the spit-up on my shoulder and asked if I had a baby. I nodded, and she burst into peals of un-doctorlike laughter, and said I didn't need a brain scan. I just needed a couple nights of uninterrupted sleep, and a WHOLE LOT LESS of the baby-feeding hormones.
Baby mush brain is not a medical diagnosis, but it sure is real.